Method of compressing elastic fluid.



'H. A. H'UMPHREY. METHOD OF COMPRESSING ELASTIC FLUID.

APPLICATION FILED 1ULY17,l 908.- RENEWED JULY 14 1917.

Patented Feb. 19, 1918.

EET- I 4 SHEETS-SH H. A. HUMPHREY. METHOD OF COMPRESSING, ELASTIC FLUID. APPLICATION man JULY 17,1908. RENEWED JULYI 4. 191 7- Patented Feb 4 SHEETS-SHEET 2.

H. A. HUMPHREY. METHOD OF COMPRESSING ELASTIC FLUID. APPLICATION FILED JULY 11, I908- RENEWED JULY 14' I917.

Patented Feb.19,1918,

4 SHEETS-SHEET 3- .liikiki w.

Z/Zzc5sea H. A. HUMPHHEY.

METHOD OF COMPRESSING ELASTIC FLUID.

APPLICATION FILED JULY 17. 190B- RENEWED JULY 14. I917. 1 25AM. Patented Feb. 19,1918;

4 SHEETS-SHEET 4.

INVENTOR ATTORNEY WITNESSES GAS PUMP COMPANY,

A CORPORATION OF NEW YORK.

METHOD OF COMPRESSING ELASTIC FLUID.

Application filed July 17, 1908, Serial No. 444,0G1.

To all whom it may concern:

Be it known that I, HERBERT ALFRED HUMPI-IREY, a subject of the King of Great Britain, residing at 38 Victoria street, \Vestminster, in the county of London, England, consulting engineer, have invented certain new and useful Improvements Relating to Methods of Compressing Elastic Fluid, of which the following is a specification.

My invention relates to improvements in the method of utilizing heat energy in the movement of liquid and utilizing the momentum or kinetic energy of the moving liquid for compressing air or gases. The object of the present invention is to provide a method whereby the raising or forcing of liquid by an expansion of an ignited combustible charge is applied to the compression or blowing of air or gas. The cycle of operation is in many respects similar or analogous to that described and claimed in my copending applications Serial No. 488,425 filed June 13, 1908 and Serial No. 655,973 filed October 21, 1911, one of which is for a method and the other for an apparatus, which applications contain claims which may be read upon the disclosure of the present application.

Referring to the drawings which illustrate merely by way of example, suitable apparatus for eiit'ecting my invention- Figure 1 is a diagrammatic vertical section of suitable apparatus for efiecting my invention.

Fig. 2 is a similar view of a modified form of apparatus.

Fig. 3 is a similar view of another modified form.

Fig. 4 is a vertical section on a somewhat enlarged scale of another modified form of apparatus, wherein the combustion and compression chambers alternate in their functions.

Fig. 5 is a vertical section of a device for controlling the pressure at the air delivery.

Fig. 6 is a vertical section of a measuring device for combustible charges.

Fig. 7 is a vertical section of a device whereby the elastic fluid compressed. is separated from the compressing mass of liquid.

Fig. 8 is a vertical section of suitable apparatus for effecting my invention showin the cooperative relationship of the several features illustrated in the other homes.

,Similar numerals refer to similar parts throughout the several views.

Specification of Letters Patent.

Patented Feb. 19, 1918.

Renewed July 14, 1917. Serial No. 180,682.

A form of the apparatus, which may be regarded as one of the simplest examples, inasmuch as it does not require that there shall be either an intake or discharge of fresh liquid at each cycle, is shown in Fig.

1, in which 1 is the combustion chamber and 3 is the compressor chamber, connected by a liquid duct or play pipe l.

In the top of chamber 1 are fitted an admission valve 5 for combustible mixture, and an exhaust valve 6 for burnt products. Suitable valve gear is used so that the exhaust valve opens when the ignited combustible mixture has expanded to substantially atmospheric pressure or other desired pressure, and is shut when the rising liquid has exhausted sutiicient of the products of combustion. The exhaust valve may conveniently be shut bv impact of the rising liquid, and remain shut until the next ignited charge expands to atmospheric pressure. The admission valve opens by suction against the action of a light spring during the period at which it is desired to introduce the charge.

In the present example the stem of the admission valve carries a pin 7 capable of engaging with the bell crank 8 pivoted at 9 and carrying a pin 10 for engaging in the slotted end of rod 11 attached to a pawl 12 pivoted at 13 on the top of the compressor chamber.

At the upper end of the compressor chamber 3 is fitted an inlet valve 14 which opens against a light spring and is locked in an open position by pawl 12, which when pulled to the right by spring 18 engages above the collar 17 on the stem of air inlet valve 14, and so keeps this valve from closing again until this pawl is released by the motion of bell crank 8 which occurs when admission valve 5 opens.

There is also fitted on the compressor chamber 3 a non-return outlet valve 15 controlled by a spring. In the outlet pipe there is also a valve 16 suitably supported and adaptedto close on a seat just above it; this valve is so loaded,

however. that the escaping air cannot close it, although the impact of the rising liquid is capable of doing so. The outlet pipe projects some distance into the compressor chamber, so that the liquid rising in the chamber can drive out air unt l the level of the liouid reaches the level oi the proiecting part 19 of the pipe. but further rise of the liquid imprisons a cushion of air in the topv of the compressor chamber and causes liquid to be forced up the outlet pipeto shut valve 16, after which, all outlets being closed in the top of the compressor-chamber, the 'imprisoned elastic cushion may be further compressed. I

The method of operation may 'now be explained. The valves being inthe position shown, it will be assumed that there is a compressed combustiblemix'ture in the topof chamber 1 abovethe level of the liquid and that there is a charge-of air or other elastic fluid in chamber 3.a'pproximately at atmospheric pressure. Explosion occurs at or about maximum compression pressure.

' Any suitable mode of ignition may be employed. The increase of pressure thus produced drives the liquid downward and outward from chamber 1 through the pipe 4: which is long enough to permit a considerable portion of the energy to be transformed 'into'momentum of kinetic energy'of the moving liquid, and causes the liquid to rise'in chamber 3, thus compressing the airtherein. It may be assumed that on the discharge side of valve 15 there already exists compressed .air at a pressurecorresponding with that at which it is desired to deliver the-air,

' so that valve 15' will not ,open' until the pressure in chamber 3 exceeds somewhat the pressure at which the air is to be delivered, after which air will be discharged past valve 1'6 which remains open and past valve 15 which is opened under the action, of the compressed air. jAccording to the circumstances of'the case, it may be that-the level of the liquid in chamber 3 will not rise above the'level of'thelower projecting p0r-- 'tion'19 of the inlet pipe, but if it does, a

cushion is formed in the top of chamber 3 above this level, and valve 16-is shut by' impact of liquid rising. in the outlet pipe,

in, which case the further use of pressure due to the-compression of the elastic cushion wi-llfor the'time being keep valve 16 shut.

Returning to the'consideration of chain ber l, when expansion has reached atmos- "pheric pressure valve 6 opens. On the col'- umn of liquid coming to res't,'the compressed "2111 1n chamber 3 forces the column of liquid downward and outward from chamber 3',

I thus reversing; the How and causing liquid toirise in chamber 1. There beinga'free opening through the'exhaust valve 6 to atmosphere, the liquid rising in chamber 1- expels the burnt products'therefromuntil. on attaining the level of valve 6 it shuts this-valve by impact and compresses an elastic: cushion in the top of chamber 1. In the meant me the energy of compression of'the 'air contained in chamber-3 havmg been expended in impartingvelocity tothe;

columliof water, the air arrives atatmospheric pressure, and the continued down-g a d f motion of? the liquid chamher causes afresh charge ofairto be drawn in 7 through valve -141, I which is sucked open against the action of a light spring. then this occurs pawl. 12, which previously rested against 'co'llarl'i, is pulled bysprmg 18 and engagesv over the collar so that it looks the inlet valve in its open position. A point in the cycle'is now reachedwherethe column ofliquid once more comes to rest and there is contained in the topof-chamber 1 a compressed elastic cushion,v in this case consisting of burnt products, or of burnt products and air, and in-chamber 3 there isalr at atmospheric pressure.

The compressed elastic cushion in the top of chamber 1 now expands, reverses the flow of liquid, and on the level oi the liquid falling until atmospheric" pressure is reached, which 'occursiw-hen thelevel is about that of valve 6', the further motion of the liquid, opens: the admission valve 5 against the action of its light spring and draws in a fresh combustible charge. Exhaust valve 6 canj not open becau'seitislooked closed in any suitable manner not shown. 7 Theadmission valve 5 n opening operates bell cranlcS,

rod 11, and pawl 12, and so permits the spring of valve 1a to "close the valve, thus stopping the discharge ofair which was occurringas the'liquid rose in chamber 3; Thls arrangement insures that'the wholeenergy or" expansion of the elastlc CLlSl110I1' shall be utilized in giving velocity to the column ofliquid untilatmospheric pressureor-thereabout is reached in chamber 1,after which admission valve 5 opens andvalve let closes as described.

apparatus toward thec'ompr'essor chamber,

until its energy'is' expended in forcing liquid to 'rise in chamber 3 and compress the air therein, and. then the liquid having once The liquid continues to move from the'combustion chamber end of the more been brought to rest, the compressed ail-in chamber 3 again reverses the-direction of how, causing liquid to again rise ihcham: her 1 and compressthefresh combustible charge thereim'which, being ignited, commences-a "fresh cycle. o I

Itshould be mentioned that in this case bell crank8 rod 11, andpawl 12'are pro;

vided for the better regulation of the worka measuring device will b je described later on. i

The charge is measured not only to'in-j sure the regular workmg'ofthe apparatus,

butto. enable the'supply of combustiblemixture to be cut off-atthe desire dpoint-soj.that

the charge drawn in can be expanded below atmospheric pressure. In this case a partial vacuum is created in chamber 1 which assists the pressure in chamber 3 in imparting the necessary kinetic energy to the liquid to give the compression stroke in chamber 1.

In order to work the apparatus just described most advantageously, the pressure at which the air or gas is delivered should not exceed a certain limit, depending upon the mean effective area of the indicator diagram taken from the power cylinder, and consequently, when other ranges of pressure are required, the apparatus is modified as will be described.

In order that the operation of the compressor may be variable in the sense that it may deliver at each cycle either a large quantity of air at relatively low pressure or a small quantity of air at relatively high pressure, the modification shown in Fig. 2 may be adopted. Here, in addition to the parts already described and similarly numbered, chamber 3 has another pipe 20 communicating with the atmosphere and pro- 'jecting for a considerable distance into the chamber. This pipe contains a valve 21 on the stem of which is a pin 22 and a collar 23 adapted to engage respectively with one arm of bell crank 2 1 and with pawl 25. The other arm of bell crank 2a is connected by rod 26 with bell crank 8, and pawl 25 is connected by rod 27 with another pawl 28, the latter being capable of engaging under collar 29, but the length of rod 27 is such that the two pawls cannot both at the same time be in engagement under their respective collars.

Two springs 30 and 31 have their ends attached to rods 26 and 27 respectively in such a manner that when rod 26 moves either to the right or the left rod 27 is pulled by the springs to follow it. There is also attached to bell crank 8 a spring, which is not shown, but acts so as to render stable the extreme positions of rod 26. Valve 21 is intended in this case to open under its own weight, its motion being limited by a spring or stop, and to be closed by the liquid rising in pipe 20 and impinging upon the valve. When admission valve 5 opens, pin 7 engaging with bell crank 8, moves rod 26 to the left where it remains until valve 21 opens and pin 22 engages bell crank 24 to move rod 26 to the right.

' The action of the modified apparatus shown in Fig. 2 may now be described. The position of the valves as shown, is correct for that part of the cycle where expansion of the ignited mixture has occurred in chamber 1, until the liquid, driven downward in chamber 1 and rising in chamber 3, has closed valve 21 which is locked shut by pawl 25. During the further expansion in chamber 1 the charge of airin chamber 3 is compressed and a portion of it is discharged under pressure intothe air delivery pipe, but as before there remains a portion to form an elastic cushion. When the liquid comes to rest the energy of expansion of the cushion in chamber 3 causes the liquid to reverse its flow driving out products of combustion through exhaust valve 6, and, when this valve is shut by impact, giving the cushion stroke. lVhen the level of liquid falling in chamber 3 is such that the pressure in chamber 3 arrives at about atmospheric pressure, valve 1 1 opens, admitting fresh air, and is locked open by pawl 12 under the action of spring 18; but valve 21 remains closed having been locked by pawl 25. Maximum cushion pressure having been attained in chamber 1 and the liquid again brought to rest, liquidL is forced downward in chamber 1 and after reaching the pressure at which the admission valve opens a fresh charge is drawn in, pawl 23 being disengaged from under collar 29 so that the admission valve can open. The liquid rising in chamber 3 during the last mentioned portion of the cycle has no work of compression to do during the first part of its movement because valve 1 1 is open to the atmosphere, but when admission valve 5 opens and so operates bell crank 8 and rod 11, pawl 12 is pulled to the left and valve 1% shuts under the action of its spring, after which the motion of the liquid is arrested by compressing air in chamber 3 and it may be expanding the charge in chamber 1, below atmosphere. The charge having been drawn into chamber 1, and bell cranks 8 and 24-, and rods 26 and 11 moved to the left, valve 5 shuts, pawl 28 engages under its collar, and pawl 25 is released from under the collar of valve 21, but as there is at this time pressure in chamber 3, valves 21 and 14 remain shut. There is now a compressed cushion of air in chamber 3 and a combustible charge in chamber 1, the pressure'ot which may be below atmosphere, and these conditions bring about a reversal of flow of the liquid which once more falls in chamber 3 and rises in chamber 1, compressing the charge in the latter. Then atmospheric pressure or thereabout is reached in chamber 3 during this part of the cycle, valve 21 will open and, by its pin engaging with bell crank 2 1, will reverse the position of bell cranks 24. and 8 and rod 26 so that they are brought back to the position shown. The compressed charge in chamber 1 is now ignited, and liquid flows from that chamber toward the compressor chamber 3, expelling air from chamber 3 through valve 21 until the liquidarrives at the level of the bottom of the pipe 20, whereupon continued rise of the liquid shuts valve 21 and the cycle is once more brought back to the point from which the operations described are repeated.

From the foregoing description it will be evident that however much air maybe-drawn into chamber 3 the quantity which is com? pressed by theworking strok occurring in chamber 1 cannot exceed the capacity of the'cliamber above the level of the bottom of pipe 20, which level maybe adjusted. q

The action of the apparatus so far clescribed may be varied to some extent by -varying the amount of liquid contained veiiiently placed close together with the ob ject that their movements may be made to control one another, Atank 52 is so placed that there maybe a free fiow of liquid to the 7 short pipes in which these valves are situated,,which pipes are continued as at 53 and 54 to communicate with the respective chambers. tion chamber and compressor chamber;

Assuming that chamber 1 is the combustion chamber, the exhaust valve willbe that shown at 6, the admission valve being shown at 5. With all the valves in the position 7 shown and a compressed combustible charge in compressing the charge of air n chamber 3, some ofwhich air is in the top of chamber 1 andacharge of air in chamber:3, ignition occurs in chamber 1 and liquid is forced downward and outward from chamber 1 toward chamber 3. Valve 51 is normally open so that liquid can escape past it into tank 52, energy is being imparted to the moving column of liquid, when, however, the ignited gases in chamber 1 have expanded to a suitable'extent the pressurebelow valve his equal to that above thisvalve, and the further expansion of these gases causes valve 50-to open against the action of spring thus admitting liquid to ratusfrom tank stem a pin 57 adapted to engage against one arm of rocking lever'59 which is pivoted at 60 and the other; arm of which engages against pin 58 on the stem'ofvalve. 51, so

that the downward movement of. valve 50 the energy of causes valve 51 to shut. Thus expansion of the ignited gases hasbeen so farmainly transformed into kinetic energy of the moving column of liquid and when valve 51 shuts this kinetic energy is utilized contained delivered under pressure past valve 15, but suflicient is rfitiiined; to; form, an, elastic cushion in As before, pipe 4 connects the combuswhile kinetic flow into the appa Valve 50 has on its which :energy isstored-for reversing the flow of the liquid. On reaching atmospheric pressure in the combustion chamber 1, eX

haust valve 6 i o'penedunder the action; of its own weight and when the reverse flow occurs valve 50 is closed by theaction of its spring and remains closed, owing; to thepressure below. thefvalve exceeding, that above it. Liquid falls in chamber 3 and rises in chamber 1 expelling the exhaust product past exhaust valve 6and' on reach ing this valve the liquid shuts it by impact, and compresses the elastic cushioncontained in the top of the chamber. About the time when the pressure in chamber 3 reaches that of the atmosphere, valve51 opens, alsovalve 14 is sucked'openby the i-alling liquid and afresh charge of air is drawninto chamber 3. Thusthe level of liquid in chamber 3 tends to bemaintained at-the level of liquid in tank 52 and valve let shuts under the pressure of its own spring. when the, pressures are adjusted. Any further movement of liquid in pipe 4' draws in fresh liqu d through valve 51. r v

The compressed elastic'cushion in the top of chamber :17 now expands. driven downward in chamber: l along' pipe 4L and escapes past valve 51 into tank 52 until, on thepre ssu're falling sufiiciently in chamber 1, fresh combustible mixture is, drawn through valve 5 until the level of liquid in chamber 1 approachesthat oi": the

liquid in tank 52. The continued movement of the column of liquid in pipe 4 causes valve 50 to open, thus shutting valve 51.

Fresh liquid is drawn in past valve 50 and:

the column of liquid proceeds to compress the air in chamber 3 until the work done brings it torest, when valve 50 shuts. Valve 5 shuts under the action of its spring after Liquid is the combustible charge has been drawn in", V

and valve 51 remains closed under the pressure now exerted upon it. Theenergy stored in the elastic cushion in chamber 3 is utilized to reverse the direction of flow, so that liquidfalls in chamber 3, rises inchamber 1 and compresses the combustible charge therein,'and toward the end of this flow of liquid" valve 51 opens again, thus bringing all the parts once more into position for repeating thecycle.

From the foregoing description it will be seen that the workingof the apparatus last described is suitable for compressing air to high pressures inasmuch as the energy of expansion of the ignited combustible gases I is at first transformed, into kinetic energy of the moving liquid and this energy may be made to operate upon arrelativel y small quantity of air and thus'compress this ailto a high pressure.

For compressing air to comparatively l w, p ythe pressure of spring 55 on (valve: 0 si l a ed1 Q th t th valve whom/1311;,

opened under its own weight and the pressure of spring 56-is increased so that this valve is normally held shut. The efiect of this change is that, when the working stroke occurs in chamber 1, valve 50 opens earlier, but as valve 51 remains closed; the liquid which is forced downward and outward from chamber 1 finds no outlet past valve 51, the compression of air starts from the commencement of the said working stroke, and a larger quantity of liquid rises in chamber 3 than in the case last considered. The energy of expansion of the ignited gases is therefore made to compress a larger volume of air, and that portion of the air which is delivered from the apparatus is delivered at a less pressure. As before, a portion of the air is retained in chamber 3 to supply the energy to reverse the flow of liquid.

After reversal and the expansion of the air cushion in chamber 3, air is drawn into this chamber until the level of the liquid approximates to that of the liquid in tank 52, liquid meanwhile escaping past valve 50 after rising in chamber 1. The level of liquid in chamber 1 will at this time be approximately the level of the liquid in tank 52, some of the products being already exhausted. The continued movement of the column of liquid in piped now causes valve 51 to open, thus closing valve 50, so that the liquid is forced to rise in chamber 1 to complete the exhaust and give the usual cushion stroke. The liquid, having come to rest, its flow is reversed under the action of the energy of the cushion in chamber 1, and the cushion expansion stroke, followed by the intake of a fresh combustible charge in this chamber, during which air in chamber 3 is compressed. Before the movement of the liquid ceases, valve 50 will open, while valve 51 remains shut. The liquid comes to rest, its flow is again reversed due to the pressure in chamber v3, and liquid flows downward in this chamber while the compressed air is expanding. The liquid which would otherwise rise in chamber 1 is at this time escaping through valve 50 into the tank, while the energy of expansion of the air in chamber 3 is being transformed into kinetic energy of the moving liquid. Nhen, however, the point in this expansion is reached at which valve 51 opens, thus shutting valve 50, the kinetic energy of the liquid is utilized in compressing the combustible charge in chamber 1. When this kinetic energyis expended the liquid comes to rest and everything is ready for the starting of a fresh. cycle by the ignition of the charge in chamber 1.

It will be seen that more liquid has entered and left chamber 3 than has entered andleft chamber 1, and that the volume of air operated upon in chamber 3 is greater than in the previous case, so that the pres sure at which the compressed air is delivered will be correspondingly less.

For some purposes it is allowable that the compressed air delivered from the apparatus should be mixed with products of cornbustion, as for instance, when the comp essed air is to be used for driving a motor, and when this is the case the pump and the compressor may be interchangeable in respect of their functions, so that combustion occurs in each alternately. Such an arrangement is shown in Fig. 1, where 113 and 114; are the chambers which serve alternately as combustion chambers and air compressor chambers,

In the top of chamber 113 are fitted an inlet valve 115 for combustible mixture, an inlet valve 117 for air, and an exhaust valve 119 for the delivery of a mixture of compressed air and burnt products. Corresponding parts 116, 118 and 120 are fitted in the top of chamber 114. Rigidly attached to the top casting of chamber 113 are pivots 121 and 122 about which move two 3-arm cranks 125 and 126. The left and right hand arms are adapted to engage with pins fitted to the stems of valves 115, 117, and 119 as shown in said Fig. l. The top arm of crank 125 is attached by springs 129 and 130 to pawls 131 and 132 respectively, and these pawls are connected by rod 133. The top arm of crank 126 is connected by springs 13% and 135 with pawls 136 and 137 respectively which are connected by rod 138. Pawl 131 is adapted to engage under a collar 139 on the stem of valve 115. Pawls 132 and 1.36 are adapted to engage under the collar 140 on the stem of valve 117 and pawl 137 is adapted to engage under the collar 14.1 on the stem of valve 119. In the outlet pipe there is, in addition to valve 119, a springcontrolled valve 142. Corresponding parts are fitted to the top of chamber 114:.

The action of the apparatus is as follows :The illustrated position of the valves is correct for that part of the cycle in which there is a compressed combustible charge in the top of chamber 113 and a charge of air and burnt products in chamber 114. Ignition now occurs in chamber 113 and the liquid is forced downward and outward from this chamber and rises in chamber 11d expelling the mixed charge at the desired pressure past valves 120 and 14:3- into the outlet pipe 157. After the liquid has attained the level of the inwardly extending pipe 152 it rises in this pipe and shuts valve 120 by impact. This valve is at once locked by'pawl 14A engaging under collar 145 and simultaneously pawl 1 16 is released from under collar 147, this motion being obtained by the tension on spring 1 :9 which, in the position shown, is greater than the tension on spring 148. The further rise of the liquid chamber 11s compresses the elastic cush ion in the top thereof and stores the -energy to give the reverse flow. When the combustible products in chamber 113 have :expandedto atmospheric pressure, valve. 117

,is sucked open and air is drawn in tomix with the products of combustion .andth-is motion of the valve moves, cranks125 and .126 throughpin 150 engaging with them. When'the suction stroke in chamber 113 is .finished and the liquid comes to rest, valve 1 117 closes under the action of its spring and pawls-132 and 136 engage under its collar and pawls 131 and 137 are disengaged from under collars 139 and 1 11 respectively, this movement being brought about by the fact that in the new position of cranks 125 and 126 the tension of springs 129 and 135 is increasedand that of springs 130 and 13-1 diminished. Valve 119 being now released falls by its own weight, and when the energy Q ,Stored in the elastic cushion i i the top of chamber 114 causes the'reverse flow, the

'liquidrising in chamber 113 has a large valve, while pawl 156 is withdrawn from under collar 1 17. The liquid having again come to rest and the pressure in chamber 113 being higher than in chamber 114, a second A outward flow .occurs fIOlIl'ChELIIllOQI 113 and the combustible charge is compressed in chamber 114 and the ignition of this charge starts a fresh cycle, in which the functions of the "chambers are reversed. Springs, not shown, are used torender stable the extreme positions of cranks 125, 126, 127 and 128,

' in the manner already referred to for other similar cases. Preferably a-measured charge of combust ble mixture is .used.

It has been assumed, in describing the cycles of the variousmodifications of apparatus, that there already existed a pressure in the outlet pipe of the compressor chamber 55.

to which it V compressed air.-

the'case in starting the apparatus, as for in- -stance,'when a reservoir for containing the on the discharge side of the outlet valve equa l was desired to deliver the This may, however, not be compressed air delivered has to be pumped up to the desired pressure. If the com- 7 pressor started without pressure in the delivery pipe the irregular working, which ,7 i would otherwise result until the desired pressure had been attained, maybe avoided by fitting to the outlet 7 to rise therein until valve'86 shuts.

pipejthe device shown in Fig. .5. A movable piston-77 is held in positionin cylinder 78' by two springs 79 and 80. On the top side of the piston air is maintained at atmospheric pressure by holes 81 which communicate with the atmosphere, while a the under side of the piston is subject to the pressure of the airin the delivery pipe 82. The piston isshowir in the position which it assumeswhen there is atmospheric pressure in 'theipipe .82. This position, due to the pressure ofspring 7 9, is

the pistons lowest position and spring is compressed to such an extent that it requires a pressure below the outlet valve 15 equivalent to the desired pressure at which air is to be delivered, to open this valve. 'As the charged begins to rise and the pressureon the under air-compressor is set to work and air is dis. past valve 15 the pressure in pipe 82 side of the piston 77 gradually increases until the desired working pressure for the compressed air is reached, when piston 7'? has been moved upward against the pressure of spring 79. This upward movement relieves the pressure, on spring SO and the springs may be so adjusted that little or no compression now remains in spring 80. Con-,

sequently valve 15 now opens when the pressure on the under side thereof is substantiallyequal to the pressure at which the air is to be delivered. By this arrangement the pressure at which valve 15 opens may be maintained practically constant from the;

starting of the apparatus until the desiredv pressure of delivery is attained, andthus the pressure conditions for each cycle remain the same,' in spiteof the varying pressures at the delivery side of the outlet valve. 1 i

A device for measuring a combust ble charge into the combustion chamber has already been alluded'to, and a description of such a device willnow be givenin connection with Fig. 6. I I i V The combustion chamber 1 is fitted with the usual inlet valve 5, but the stem of this valve has a connection, shown diagrammatically as a rod 83, with the stem of valve 84 placed in the combustible inlet pipe, so." i

that when valve5 opens valve Set is closed. The combustible inlet pipe 87 is also connected with a measuring chamber 85, in the top of which there is a valve 86 adapted to be shut byimpact ofliquid upon it. Measuring chamber 85-is connected with .a supply of water not shown which is open 'to' the atmosphere in such a manner, that the normal level of water in themeasuring chamber may be adjusted.

The action of the apparatus is as fol lows 7 When valve the suction in 5 opens, valve Stis closed and chamber :85 causes the liquid bythe im--.

pact of liquid upon it.. Thus, valves 84: and

i may be connected 86 being both closed, no more combustible mixture can be taken into chamber 1, and when the pressure in this chamber and in the combustible inlet pipe 87 has risen suf ficiently, valve 5 will shut under the action of its spring. This movement of valve 5 opens valve 8%, and further combustible mix ture flows into pipe 8?. Valve 86 falls by its own weight, and the liquid in chamber 85,

in falling to its normal level, draws a measured quantity of combustible mixture into the chamber.

The seats of valves 5 and 84: are prolonged in such a manner as to cause these valves to act partly as piston valves, so that valve 81 may be shut by the time valve 5 is open.

It will be seen that by altering the normal level of liquid in chamber 85, the quantity of the measured charge taken in can be varied.

It is well known that pistons of difierent areas may be used to convert high pressure energy into low pressure energy, or vice versa, and it is obvious that this fact can be utilized in connection with the present invention. Thus, if low pressure air in large volume is required, the liquid, instead of rising and falling in an air compressor chamber, may act directly upon a piston 110 (Fig. 7) fitted in a turned portion of the pipe in which the liquid moves. This small piston with a larger piston 111 and the latter may move in an air compressor chamber 112. 14 and 15 are inlet and outlet valves respectively fitted in the chamber and so situated that piston 111 in moving to its top position closes both inlet and outlet and imprisons a cushion of air in the top of the chamber. Similarly, when the piston moves to its bottom position, it closes the vents to the atmosphere 158 and 159 and so cushions the air imprisoned in the bottom of the chamber and prevents the piston striking the chamber. The action of the apparatus is precisely on the same lines as when liquid rises and falls in the chamber, the only difference being that, instead of the liquid rising and shutting valve 16 in chamber 3, to imprison, an air cushion which stores the energy for reversing the flow of liquid, piston 111 cuts off communication by covering the inlet and outlet pipes in cham-v ber 112 and thus imprisons an air cushion in the top of this chamber. The air cushion in the bottom of the chamber is not intended normally to come into play as the lowest position to which the piston normally reaches is that shown in Fig. 7.

Throughoutthe present specification the elastic cushion which is compressed in the air compressor to furnish the'energy for the return flow of liquid has been spoken of as a cushion of air, but it has been shown in my application No.

1910, that in the case of the pump the elastic cushion may be obtained by a piston or valve in a branch chamber opening'into the combustion chamber, that side of the piston which is not presented to the chamber being acted upon by a spring or by compressed air or equivalent device. It is obvious that a similar method may be employed in connection with the present invention without departing from the spirit thereof.

What I claim is 1. The method of compressing air or other elastic fluid which consists in propelling a mass of liquid outwardly from a combustion chamber by the energy of expansion of an ignited combustible charge, allowing the said outwardly propelled mass to compress elastic fluid in a compression chamber, allowing some of the energy of this compression to cause the said mass to move inwardly to compress an elastic cushion in the combustion chamber and to cause an intake of elastic fluid in the compression chamber, allowing the energy of the compression of the cushion to cause the mass to flow outwardly again to entrain a fresh combustible charge and compress the admitted elastic fluid, and allowing the energy of the compression of the said admitted fluid to cause the mass to flow toward the combustion chamber to compress the fresh charge.

2. The method of compressing air or other elasticfluid, which consists vin propelling a mass of liquid outwardly from a combustion chamber by the energy of expansion of an ignited combustible charge, allowing the said outwardly propelled mass, while a portion of the liquid is raised to a height, to compress elastic fluic in a compression chamber, allowing some of the energy of this compression, aided by the liquid which has been elevated, to cause the said mass to move in wardly to compress an elastic cushion in the combustion chamber, and to cause an intake of elastic fluid in the compression chamber, allowing the energy of the compression of the cushion to cause the mass to flow outwardly again to entrain a fresh combustible charge and. compress the admitted elastic fluid, and allowing the energy of the compression of the said admitted fluid to cause the mass to return toward the combustion chamber to compress the fresh combustible charge.

3. The method of compressing air or other elastic fluid which consists in propel ling a mass of liquid outwardly from a com bustion chamber to compress elastic fluid in a compression chamber, allowing some of the energy of compression to cause the said mass to move inwardly to compress an elas tic cushion in the combustion chamber and to cause an intake of elastic fluid in the compression chamber, allowing the energy of the compression of the cushion tov cause compression chamber,

the mass to flow outwardly again to entrain a fresh combustible charge and compress the admitted elasticfluid allowing the energy of the compression of theisaid'admitted'fluid to cause the mass to flow toward the combustion chamber to compress the fresh combustible charge, and varying the volume of elastic fluid compressed by varying the volume of liquid that is forced into the compression space in the said compression chamber by the saidenergy of expansion.

4, Themethod, of compressing air or other elastic fluid which consists in propelling a massof liquid outwardly from a combustion chamber to compress elastic fluidi'n a com 'pression'chamber connected with the coinbustion chamber, allowing the energy of compression to cause the said mass to move inwardly to compress an elastic cushion in the combustionchamber and to cause an intake of elastic fluid in the compression chamber, allowing the energy of thecompression of the cushion to cause the mass to flow outwardly again to entrain a fresh combustiblecharge and compress the admitted elastic fluid, allowing'the energy of the compression of the admitted fluid to cause the massto'flow toward the combustion chamber a to compress the fresh combustible charge,

and varying the volume of the air or elastic fluid compressed by allowing liquid to be Jtaken'in and rejected during a cycle.

'5. The method of compressing air or other elastic fluid which consists in propelling a mass of liquid outwardly from a combus tion chamber to compress elastic fluid in a 7 compression chamber connected with the" combustion chamber, allowing some of the fluid to cause the mass to flow'towardthe combustion chamber to compress the fresh combustible charge, and varying the volume of the elastic fluid compressed by allowing some of the elastic fluid taken in to be re jected again previous to compression.

c r 6. The'method which consistsin reeiproeating a column of liquid, witha velocity sutticiently limited to preserve the coherence of the column and having sufficientv bulk and path of travel to acquirev useful momentum, by applying the actuating force" of an expansible medium to each end of the column at required intervals respectively, and utilizing the pressure of'the liquid columnfdue to the momentum it'acqui'res in its reciprocating'movements.

' compress an elasticfluidand deliver m ee 7. The methodwhich consistsin rccipro eating a, column of" liquid with a velocity sufliciently limited to preserve the coherence 'of the column and having suflicient bulk and path of travel to acquire; useful 'mo-f inentum by applying the actuating force of an expansible medium to each end of the column at required intervals respectively and utilizing said momentum.

8. The method'which consists in; recipro;

eating a column of liquid with a velocity suiliciently limited to preserve thecoherence of the column and having sufficient bulk and path of travel to acquire useful momentum by applying the actuating force of an expansible medium :to each end of the column at required intervals respectively and utilizing said momentum to compress an elastic medium a Y 9. The method of compressing elastic fluid which consists in reciprocating a body of liquid, the first outward movement ofsaid reciprocation being due to, the expansive force of an ignited combust ble charge, utilizing the momentum of said outward move- .ment to compressftheelastic fluid and to deliver aportlon thereof, utllizing the ex; 'pansion of therema ning compressed fluid to cause a returninovement'of the liquid and automatically regulating the pressure of compressed fluid at the discharge, during the earlier cy les until normal pressure conditions are established; 7

10. The method which consists in reciprocating a column of liquid with a velocity sufiiciently limited to, preserve the coherence of the column and'having sufficient volume and pathof travel to acquire useful momentum, one outstrokeimovement of said reciprocation due to anexpan'sive'force utilizing said momentum of said outstroke to compress an elastic fluid and deliver a por-' tion thereof. g s 11. The method which consists in reciprocating a column of liquid with a velocity sufliciently limited to preserve thecoherence andpath oftra-vel to acquire useful'momentum, one outstrokei movementof said reciprocation due to an expansive force, ut1- lizing the momentum of said outstroke' to aiporof the column and having sufiicient volume tion thereof, and utilizing the energy of another portion of said compressed elastic fluid 1n causing a return movement of the liquid.

12. The method which consists-in recip V rocating a column of liq uidof suliicient volume and path of travel to acquire use ful momentum, one movementof said re- .ciprocation due to an expansive"force,*uti-,

liz'in'g -said momentum'to compress an elase tic fluidand-deliver a portion} thereof and varying the amount of elastic fluid compressed r j I 13. The method which consists in reciprocating a column of liquid of sufficient volume and path of travel to acquire useful momentum, one movement of said reciprocation due to an expansive force, utilizing said momentum to compress an elastic fluid and deliver a portion thereof and varying the amount of elastic fluid compressed while the expenditure of initial energy remains constant.

14-. The method of compressing elastic fluid which consists in reciprocating a body of liquid, the first outward movement of said reciprocation being due to the expansive force of an ignited combustible charge, utilizing the momentum of said outward movement to compress the elastic fluid and to deliver a portion thereof, utilizing the expansion of the remaining compressed fluid to cause a return movement of the liquid, and introducing and discharging by regulatable means liquid for controlling the volume of compressed elastic fluid discharged.

15. The method of compressing elastic fluid which consists in reciprocating a body of liquid, the first outward movement of said reciprocation being due to the expansive force of an ignited combustible charge, utilizing the momentum of said outward movement to compress the elastic fluid and to deliver a portion thereof, utilizing the expansion of the remaining compressed fluid to cause a return movement of the liquid, and introducing and discharging by regulatable means liquid for controlling the pressure of compressed elastic fluid discharged.

16. The method of compressing elastic fluid which consists in reciprocating a body of liquid, the first outward movement of said reciprocation being due to an expansive force, utilizing the momentum of said outward movement to compress the elastic fluid and to deliver a portion thereof, utilizing the expansion of the remaining compressed fluid to cause a return movement of the liquid and introducing and permitting the escape by regulatable means of fresh elastic fluid for controlling the pressure or the volume of said fluid compressed and delivered.

17. The method of compressing elastic fluid which consists in reciprocating a body of liquid, the first outward movement of said reciprocation being due to the expansive force of an ignited combust ble charge, utilizing the momentum of said outward movement to compress the elastic fluid and to deliver a portion thereof, utilizing the expansion of the remaining compressed fluid to cause a return movement of the Copies of this patent may be obtained for five cents each,

liquid and utilizing measuring means for securing the introduction into the combustion chamber at each cycle of a definite measured combustible charge.

18. The method which consists in reciprocating a column of liquid of sufflcient volume and path of travel to acquire useful momentum, one movement of said reciprocation due to an expansive force, utilizing said momentum to compress an elastic fluid and deliver a portion thereof, and varying the pressure of compression of said elastic fluid.

19. The method which consists in reciprocating a column with a velocity sufficiently limited to preserve the coherence of the column and having liquid of sufficient volume and path of travel to acquire useful momentum, one movement of said reciprocation due to an expansive force, utilizing said momentum to compress an elastic fluid and deliver a portion thereof and definitely measuring the expansible charge used in giving the initial movement of reciprocation.

20. The method which consists in reciproeating a column of liquid of suflicient volume and path of travel to acquire useful momentum, one movement of said reciprocation due to an expansive force, utilizing said momentum to compress an elastic fluid and deliver a portion thereof, measuring the expansible charge used in giving the initial movement of reciprocation and causing a partial vacuum at the rear of the outstroke introducing said charge to facilitate the return stroke.

21. The method which consists in reciprocating a column of liquid of sufficient volume and path of travel to acquire useful momentum, one movement of said reciprocation due to an expansive force, utilizing said momentum to compress and discharge an elastic fluid, and maintaining a constant pressure at the discharge.

22. The method which consists in reciprocating a column of liquid with a velocity ufliciently limited to preserve the coherence of the column and having sufficient volume and path of travel to acquire useful momentum, one movement of said reciprocation due to an expansive force, utilizing said momentumto compress and discharge an elastic fluid and maintaining automatically a constant pressure at the discharge.

In testimony whereofl: have signed my name to this specification in the presence of two subscribing witnesses.

HERBERT ALFRED HUMPHREY.

Witnesses:

WALTER J. SKERTEN, Josnrn MILLARD.

by addressing the Commissioner of Eatents,

Washington, I). G. 

